Method of purifying or cleansing a body of liquid

ABSTRACT

A method of purifying or cleansing a body of liquid is provided. The body of liquid, typically water, containing one or more contaminants is contacted with a biocide comprising hydrogen peroxide (H 2 O 2 ) in combination with a catalyst for enhancing the activity thereof, the catalyst preferably comprising a superoxidedismutase formed from the combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn) so as to eliminate, in whole or in part, the contaminant(s). The biocide formulation may be an aqueous solution or suspension of biocide, or may be a solid composition in the form of a tablet which is soluble in water. The tablet contains a compound which reacts with H 2 O to form hydrogen peroxide (H 2 O 2 ) and also typically contains oxides, sulphates or phosphates of Cu, Mn and Zn and silver oxide or silver acetate, together with a binder and/or effervescent.

BACKGROUND OF THE INVENTION

[0001] THIS invention relates to a method of purifying or cleansing a body of liquid, in particular a body of water, containing one or more contaminants, and to a biocide formulation for use in such method.

[0002] The treatment of water is required in many aspects of everyday life. These range from swimming pools, spas, Jacuzzis and other similar recreational applications to industrial and agricultural applications, to name but a few. Many different compositions and methods are provided for treating the water which is suitable for human and animal consumption. For instance, chlorine or bromine based salts are often used in swimming pools, spas, Jacuzzis, and the like. These products tend not only to be relatively expensive, but may also be hazardous and inconvenient to handle. There is, thus, always a need for new methods and formulations for treating water.

SUMMARY OF THE INVENTION

[0003] According to a first embodiment of the invention, a method of purifying or cleansing a body of liquid, in particular a body of water, containing one or more contaminants, includes the steps of contacting the body of liquid with a biocide comprising hydrogen peroxide (H₂O₂) in combination with a catalyst for enhancing the activity thereof, the catalyst preferably comprising a superoxidedismutase formed from the combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn) so as to eliminate, in whole or in part, the contaminant(s).

[0004] The biocide formulation is preferably an aqueous solution or suspension of the biocide.

[0005] The H₂O₂, is typically present in the biocide solution or suspension in an amount of about 0.000003% to about 15% v/v, preferably about 0.003% to about 3% v/v, in particular about 0.3% v/v.

[0006] The Cu, Mn and Zn are typically present in an amount of about 100 ppb to about 1000 ppm, preferably about 3 to 20 ppm, in particular about 10 ppm.

[0007] The Ag is typically present in an amount of about 100 ppb to about 1000 ppm, preferably about 3 to 30 ppm, in particular about 20 ppm.

[0008] According to a second embodiment of the invention, a method of purifying or cleansing a body of liquid, in particular a body of water, containing one or more contaminants, includes the steps of contacting the body of liquid with a biocide comprising a compound which reacts with H₂O to form hydrogen peroxide (H₂O₂), in combination with a catalyst for enhancing the activity of the H₂O so formed, the catalyst preferably comprising a superoxidedismutase formed from the combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn) so as to eliminate, in whole or in part the contaminant(s).

[0009] Th biocide formulation may be a solid composition in the form of a tablet which is soluble in water.

[0010] An example of the compound which reacts with H₂O to form H₂O₂ is odium perborate (NaBO₃). The compound is present in the tablet in sufficient concentration to form an amount of H₂O₂ when dissolved in the body of liquid of about 0.000003% to about 15% v/v, preferably about 0.003% to about 3% v/v, in particular about 0.3% v/v.

[0011] The tablet further contains Cu—, Mn—, and Zn oxides, sulphates, phosphates or the like. These compounds typically release the elemental Cu, Mn and Zn in an amount of about 100 ppb to about 1000 ppm, preferably about 3 to 20 ppm, in particular about 10 ppm, when the tablet is dissolved in the body of liquid.

[0012] The tablet also contains silver oxide (Ag₂O), silver acetate (CH₃COOAg) or the like, which produces elemental Ag when dissolved in H₂O, typically in an amount of about 100 ppb to about 1000 ppm, preferably about 3 to 30 ppm, in particular about 20 ppm, when the tablet is dissolved in the body of liquid.

[0013] The Cu, Mn, Zn and Ag combine to form the superoxidedismutase.

[0014] The tablet further includes a binder and/or effervescent.

[0015] The binder may be sodium silicate (Na₂SiO₃) or any other suitable binding agent which is soluble in water.

[0016] The effervescent may be selected from sodium bicarbonate, tartaric acid, citric acid, sodium tartrate or sodium citrate, or any combination thereof.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0017] The invention provides a method and biocide formulation for eliminating in whole or in part contaminants in a body of liquid, in particular a body of water.

[0018] The method comprises contacting the contaminated water, for instance, with a biocide comprising hydrogen peroxide (H₂O₂) in combination with a catalyst for enhancing the activity thereof. The preferred formulation of the invention is preferably an aqueous solution or suspension including a catalyst comprising a superoxidedismutase formed from the combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn) so as to eliminate, in whole or in park the contaminant(s)* The H₂O₂ is typically present in the biocide solution or suspension in an amount of about 0.000003% to about 15% v/v, preferably about 0.003% to about 3% v/v, in particular about 0.3% v/v.

[0019] The Cu, Mn and Zn are typically present in an amount of about 100 ppb to about 1000 ppm, preferably about 3 to 20 ppm, in particular about 10 ppm.

[0020] The Ag is typically present in amount of about 100 ppb to about 1000 ppm, preferably about 3 to 30 ppm, in particular about 20 ppm.

[0021] Alternatively, the biocide is in the form of a tablet which is soluble in water. The biocide includes sodium perborate (NaBO₃) or any other suitable substance which reacts with H₂ to form hydrogen peroxide (H₂O₂).

[0022] The tablet further includes Cu—, Mn— and Zn oxide, sulphate or phosphate, which form elemental Cu. Mn and Zn when dissolved in the water. Ag₂O or CH₃COOAg is also present in the tablet to form elemental Ag when dissolved in the water. The Cu, Mn, Zn and Ag combine to form the superoxidedismutase.

[0023] The tablet also includes either a binder or an effervescent. The binder is typically Na₂SiO₃, and the effervescent typically comprises:

[0024] sodium bicarbonate (54.25%);

[0025] tartaric add (37.5%);

[0026] citric acid (6.25%);

[0027] sodium tartrate (1%); and

[0028] sodium citrate (1%).

[0029] The biocide formulation and method may be used to treat water, for instance, in a wide range of applications. These include recreational applications such as swimming pools, spas, Jacuzzis, and so called supertubes, for example, agricultural applications such as crops e.g. sugar and other consumable crops, dams and hydroponics water supplies for example, in plant and animal applications such as Koi ponds, fresh water fish ponds and tanks, cattle and other livestock drinking water, and water supplies for indoor plants and outdoor plants, for example, industrial and commercial applications such as industrial plant water system, water cooling towers, water based air conditioning units, and industrial and commercial waste water, for example, sewage treatment such as raw sewage, sewage management systems and sewage spills, for example, and water for consumption such as bottled water, military deployment water purification systems, re-circulated/purified drinking water from waste water systems, water tanks and dams, for example. The effervescent tablet formulation of the biocide is preferably used to treat small bodies of water having a volume of 20 litres or less, preferably 5 litres or less, and more preferably 2 litres or less.

[0030] The contaminants to be treated are typically microorganimsms including anaerobic bacteria such as desufovibrio, leuconostc and desuffuicans, aerobic bacteria such as aerobacter, flavobacterium, faecal coliforms, oyptosporidiumn, bacillus mycoides, bacillus subtirls and enterobacterium, viruses such as cholera and fungi such as yeast, candidia and the like.

[0031] In order to evaluate the efficacy of the method and formulation of the invention, a leading water treatment company carried out the following independent tests on contaminated water using the formulation of the invention. Individual samples of the contaminated water were taken and dosed with different concentrations of a biocide formulation containing 0.06%, 0.03%, 0.02%, 0.01% and 0.004% v/v H₂O₂ and a superoxidedismutase catalyst consisting of 10 ppm Cu. Zn and Mn, and 20 ppm Ag. The test samples were then plated out on agar plates and cultivated to establish growth versus “kill rate” over a 24-hour period. The control sample (to which no biocide had been added) measured 600 000 colonies at the 4 hour mark and a further 100 000 colonies at the 24 hour mark. The results of the test samples are set out in the table below. Dose concentration of Efficacy (percentage Efficacy (percentage biocide formulation microorganisms microorganisms (ppm) irradicated) - 4 hrs irradicated) - 24 hrs 600 100 100 300 99.22 99.97 200 98.65 99.96 100 93.24 94.10 40 91.89 91.00

[0032] In the light of the above test results, it is believed that the method and biocide formulation of the invention are capable of eliminating, at least in part micro-organisms form a body of liquid such as water. The chemical compounds for the biocide are not only readily available and cost effective, but are human safe, non-toxic, non-allogenic, fast acting, eco-friendly and provided in quantities which are well below OSHA regulations. 

1. A method of puking or cleansing a body of liquid containing one or more contaminants, the method including the step of contacting the body of liquid with a biocide comprising hydrogen peroxide (H₂O₂) in combination with a catalyst br enhancing the activity of, so as to eliminate, in whole or in part, the contaminant(s).
 2. A method according to claim 1, wherein the liquid is water.
 3. A method according to either of claims 1 or 2, wherein the catalyst comprises a superoxidedismutase formed from a combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn).
 4. A method according to any one of claims 1 to 3, wherein the biocide formulation is an aqueous solution or suspension of the biocide.
 5. A method according to claim 4, wherein the H₂O₂ is present in the biocide solution or suspension in an amount of about 0.000003% to about 15% v/v.
 6. A method according to claim 5, wherein the H₂O₂ is present in the biocide solution or suspension in an amount of about 0.003% to about 3% v/v.
 7. A method according to any one of claims 3 to 6, wherein the Cu, Mn, Zn and Ag are present in an amount of about 100 ppb to about 1000 ppm.
 8. A method of purifying or cleansing a body of liquid containing one or more contaminants, the method including the step of contacting the body of liquid with a biocide comprising a compound which reacts with H₂O to form hydrogen peroxide (H₂O₂), in combination with a catalyst for enhancing the activity of the H₂O₂ so formed, so as to eliminate, in whole or in part the contaminant(s).
 9. A method according to claim 8, wherein the liquid is water.
 10. A method according to either of claims 8 or 9, wherein the catalyst comprises a superoxidedismutase formed from a combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn).
 11. A method according to any one of claims 8 to 10, wherein the biocide formulation is a solid composition in the form of a tablet which is soluble in water.
 12. A method according to any one of claims 8 to 11, wherein the compound which reacts with H₂O to form H₂O₂ is sodium perborate (NaBO₃).
 13. A method according to either of claims 11 or 12, wherein the tablet further contains Cu—, Mn—, and Zn oxides, sulphates or phosphates, and silver oxide (Ag₂O) or silver acetate (CH₃COOAg), which release elemental Cu, Mn, Zn and Ag, respectively when dissolved in the body of liquid.
 14. A method according to any one of claims 11 to 13, wherein the tablet further includes a binder or effervescent.
 15. A biocide formulation for cleansing or puking a body of liquid, the biocide formulation including: hydrogen peroxide (H₂O₂); and a catalyst for enhancing the activity of H₂O₂.
 16. A biocide formulation according to claim 15, wherein me catalyst comprises a superoxidedismutase formed from a combination of elemental copper (Cu), silver (Ag), manganese (Mn) and zinc (Zn).
 17. A biocide formulation according to either of claims 15 or 16, wherein the H₂O₂ is present in an amount of about 0.000003% to about 15% v/v; and Cu, Mn, Zn and Ag are present in an amount of about 100 ppb to about 1000 ppm.
 18. A biocide formulation according to claim 17, wherein the H₂O₂ is present in an amount of about 0.003% to about 3% v/v, the Cu, Mn and Zn are present in an amount of about 3 to 20 ppm; and the Ag is present in an amount of about 3 to 30 ppm.
 19. A biocide formulation for cleansing or purifying a body of liquid, the biocide formulation including: a compound which reacts with H₂O to form hydrogen peroxide (H₂O₂); and a catalyst for enhancing the activity of the H₂O₂ so formed.
 20. A biocide formulation according to claim 19, which further includes Cu—, Mn—, and Zn oxides, sulphates or phosphates which release elemental Cu, Mn and Zn when dissolved in the body of liquid; silver oxide (Ag₂O) or silver acetate (CH₃COOAg) which releases elemental Ag when dissolved in the body of liquid; and a binder or effervescent. 